Effects of administration of phentonium bromide on opioid withdrawal syndrome in rats.
This study has tested whether phentonium bromide, a quaternary ammonium anti-muscarinic agent, could reverse the signs of precipitated opioid withdrawal. Rats were treated with either saline or morphine for 4 days, after which half the rats received naloxone and half saline. Each animal also received one of four doses of phentonium bromide (0, 1, 3 and 9 mg kg(-1), i.p.). Administration of phentonium bromide in rats receiving naloxone after chronic morphine treatment reduced the intensity of withdrawal signs such as increased defecation or micturition, salivation and wet-dog shakes, and elevated the nociceptive threshold values. The effects of administration of phentonium bromide might result from its anti-muscarinic activity interfering peripherally with the mechanisms involved in the regulation of the withdrawal symptoms. The use of this drug is thus suggested as a possible means of controlling some of the signs observed during the acute phase of opioid withdrawal in heroin addicts.
Pinelli
A
A
Department of Pharmacology, Chemotherapy and Medical Toxicology, Milano, Italy.
Trivulzio
S
S
Tomasoni
L
L
D000701:Analgesics, Opioid / Q000009:adverse effects*; D000704:Analysis of Variance; D000818:Animals; D001286:Atropine Derivatives / Q000494:pharmacology / Q000627:therapeutic use*; D001831:Body Temperature / Q000187:drug effects; D003672:Defecation / Q000187:drug effects; D008297:Male; D015394:Molecular Structure; D009020:Morphine / Q000009:adverse effects*; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D010276:Parasympatholytics / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011976:Receptors, Muscarinic / Q000187:drug effects; D013375:Substance Withdrawal Syndrome / Q000188:drug therapy* / Q000209:etiology; D014554:Urination / Q000187:drug effects
D000701:Analgesics, Opioid; D001286:Atropine Derivatives; D009292:Narcotic Antagonists; D010276:Parasympatholytics; D011976:Receptors, Muscarinic; C100112:fentonium; D009270:Naloxone; D009020:Morphine